1. Technical Field
The present invention relates to a printing device that prints on recording paper delivered from a paper roll stored inside, and to a roll paper loading mechanism for loading roll paper into the printing device.
2. Related Art
Printing devices equipped with a roll paper loading mechanism include drop-in type printers that have an opening for loading roll paper rendered in the front of the printer so that the user can tilt an access cover that closes this opening forward and drop the roll paper into the printer.
Japan Patent No. 3855591 teaches a roll paper printer that has this type of roll paper loading mechanism. When the roll paper cover that closes the opening for loading roll paper in this printer is tilted forward, a linkage mechanism that supports the roll paper cover also swings forward. A roll paper loading unit into which the roll paper can be dropped with the rotational axis thereof extending transversely is rendered inside the printer.
The roll paper loading unit in Japan Patent No. 3855591 has a bottom, back, front, and left and right side panels, and the gap between the left and right side walls can be adjusted according to the size of the roll paper. The roll paper loading unit has a roll paper holder that can rotate forward in conjunction with operation of the linkage mechanism when the roll paper cover opens. As a result, when the roll paper cover is opened, one of the side walls and part of the bottom panel of the roll paper loading unit also move forward when the front panel part of the roll paper loading unit rotates to the front. The opening for loading roll paper thus actually becomes larger, and there is no need to lift the roll paper over the front panel part when dropping the roll paper inside. The roll paper can therefore be held substantially level when it is dropped in from the front of the printer. The roll paper loading position also moves forward, making loading the roll paper simple.
Holding the roll paper between and by the left and right side walls of the roll paper loading unit to apply side pressure to the paper roll has also been proposed as a means of preventing the roll paper from rising when recording paper is pulled from the paper roll loaded in the roll paper loading unit.
However, because the gap between the left and right side walls narrows to almost the same width as the roll paper when side pressure is applied to the roll paper by the left and right side walls, the opening to the roll paper loading unit also becomes narrow, making loading the roll paper more difficult. More particularly, when as in the printer described in Japan Patent No. 3855591 one of the side walls does not move from inside the printer, positioning the roll paper widthwise can be difficult when loading the paper, and the paper roll can easily collide with the front edge of the stationary side wall when it is dropped in. This makes pushing the roll paper into the loading position difficult. Furthermore, while the one side wall on the roll paper holder side moves forward with the roll paper cover in the printer taught in Japan Patent No. 3855591, it does not move so far that it is exposed on the outside of the printer case. Positioning to this side wall is therefore also not easy, and the roll paper being loaded can easily collide with the front edge of the side wall.
A roll paper loading mechanism and a printing device according to the invention enable loading roll paper easily even when the width of the opening to the roll paper loading unit is narrow.
A first aspect of the invention is a roll paper loading mechanism including a linkage mechanism that supports an access cover for opening and closing a roll paper loading opening formed in a device case so that the access cover can pivot on one end and move between a closed position where the opening is closed and an open position to which the other end swings away from the opening; and a roll paper loading unit formed so that when the access cover is open the roll paper can be dropped in with the axis of rotation transverse. The roll paper loading unit includes two side panels disposed to hold the roll paper therebetween in the direction of the axis of rotation when the access cover is closed. One of the two side panels is a movable side panel that can pivot to a position where at least part of the side panel is exposed from the opening outside the device case when the access cover is opened.
When the access cover is opened in this aspect of the invention, the roll paper can be positioned outside the device case to at least one of the side panels of the roll paper loading unit. If the side panel protrudes outside the device case, the operator can easily find the position for aligning the roll paper, and loading failures such as mistakenly setting the roll paper to an edge of the opening or another member inside the opening can be prevented. In addition, because the roll paper can be dropped in along one side panel from outside the device, roll paper can be easily dropped in even if the width of the opening is small. More specifically, roll paper can be easily dropped in even when the width of the roll paper storage space for applying side pressure is narrowed to substantially the same width as the roll paper.
In another aspect of the invention, when the other of the two side panels is a stationary side panel fixed inside the device case, a roll paper guide tab that extends away from the movable side panel as the projection to the side of the opening increases is preferably formed on the end part of the stationary side panel on the opening side.
When such a roll paper guide tab is provided, the roll paper dropped in from a position offset to the outside of the opening from the stationary side panel can be made to hit the inclined face of the roll paper guide tab so that the roll paper moves along the roll paper guide tab to the correct loading position. The roll paper can therefore be easily positioned to the stationary side panel that is not exposed outside the device case, and loading the roll paper is even easier.
Further preferably in another aspect of the invention, the stationary side panel is affixed so that the end part where the roll paper guide tab is formed is a free end that can move toward and away from the movable side panel.
With this aspect of the invention, the link can move by deflecting the stationary side panel even when roll paper guide tab interferes with the path of the link of the linkage mechanism when the access cover opens and closes.
Further preferably in another aspect of the invention, when the linkage mechanism includes a link member disposed along the opposite side of the stationary side panel as the movable side panel, and the link member is configured to descend in the direction in which the access cover pivots when the access cover opens, and overlap the end part of the stationary side panel on the open side, the roll paper guide tab is preferably formed on a part of the stationary side panel separated from the overlap position.
When roll paper is loaded in this aspect of the invention, there is no interference between the link member and the roll paper guide tab, and the stationary side panel does not deflect. The size of the opening from which the roll paper is dropped in therefore does not narrow when the roll paper is loaded.
Further preferably, the part of the roll paper guide tab protruding farthest to the side of the opening is positioned at least the thickness of the stationary side panel from the main part of the stationary side panel in the direction away from the movable side panel.
In this aspect of the invention the distance between the distal end of the roll paper guide tab and the movable side panel is equal to or greater than the distance between the movable side panel and the link member disposed along the opposite side of the stationary side panel as the movable side panel. The roll paper can therefore be positioned to the link member that drops down when the access cover is opened, and if the roll paper is dropped in along the link member, the roll paper strikes the sloped face of the roll paper guide tab and the roll paper is moved by the roll paper guide tab toward the side of the movable side panel. The roll paper can therefore be reliably loaded between the stationary side panel and the movable side panel.
Further preferably, the roll paper loading mechanism also has an urging member that urges the link member to the side of the stationary side panel so that the link member and the stationary side panel touch.
With this aspect of the invention the distal end of the roll paper guide tab can be reliably separated further from the movable side panel than the link member, or positioned the same distance from the movable side panel. Therefore, when roll paper is dropped in along the link member, the roll paper can be reliably shifted by the roll paper guide tab.
In another aspect of the invention, the part of the stationary side panel where the roll paper guide tab is formed deflects in the direction toward the movable side panel due to interference between the roll paper guide tab and the link member when the access cover opens and closes; the movable side panel moves between a first position and a second position on the stationary side panel side of the first position in conjunction with the access cover opening and closing, moves to the first position when the access cover is in the open position, and moves to the second position when the access cover is in the closed position; and the distance between the first position and the second position is preferably greater than or equal to the deflection of the stationary side panel toward the movable side panel caused by interference between the roll paper guide tab and the link member.
When the access cover opens and closes in this aspect of the invention, the width of the opening for dropping in the roll paper will not become narrower than the width of the roll paper storage space when loading is completed because the movable side panel moves in the same direction as the direction in which the stationary side panel deflects when the stationary side panel deflects. As a result, interference with the roll paper when loading the roll paper will not result in such problems as being unable to move the roll paper loading mechanism or load the roll paper.
Further preferably in another aspect of the invention, the link member has a roll guide surface that is opposite the movable side panel and extends straight toward the end part of the stationary side panel, and is formed on a part of the stationary side panel that protrudes from an end part on the open side toward the access cover in the open position.
In this aspect of the invention the roll paper can be guided in a straight line by the link member. In addition, because one end can be guided by the movable side panel and the other end can be guided by the link member, the roll paper does not easily become biased to the loading direction. The roll paper can therefore be prevented from being dropped in at an angle between the stationary side panel and the movable side panel.
Further preferably, a guide boss that protrudes from the roll guide surface toward the movable side panel is disposed to the link member at an intermediate position in the guiding direction of the roll guide surface.
Because the roll paper must ride over the guide boss when such a guide boss is provided, the roll paper will either ride over the guide boss to the stationary side panel side and drop in, or will roll to the front of the guide boss and drop out. The roll paper will therefore not stop at some intermediate position when dropped in.
Further preferably in another aspect of the invention, when the opening is formed in the front of the device case, and the link member moves to the front of the device case and protrudes from the front end of the stationary side panel to the front of the device case when the access cover is opened, the top of the protruding link member is an inclined guide surface that slopes down toward the front of the device case.
When the roll paper cannot be positioned to the inside surface of the link member when it is dropped in and the roll paper falls onto the top of the link member, the roll paper will not drop toward the roll paper storage unit while improperly positioned to the stationary side panel and movable side panel, and will quickly roll toward the front of the device case and fall out. The roll paper will therefore not stop at some intermediate position when dropped in, and can be quickly repositioned and dropped in.
Another aspect of the invention is a printing device including a device case that houses a print mechanism, an opening formed in the device case for loading roll paper, an access cover for opening and closing the opening, and the roll paper loading mechanism described above.
When the access cover is opened in this aspect of the invention, the roll paper can be positioned outside the device case to at least one of the side panels of the roll paper loading unit. If the side panel protrudes outside the device case, the operator can easily find the position for aligning the roll paper, and loading failures such as mistakenly setting the roll paper to an edge of the opening or another member inside the opening can be prevented. In addition, because the roll paper can be dropped in along one side panel from outside the device, roll paper can be easily dropped in even if the width of the opening is small. More specifically, roll paper can be easily dropped in even when the width of the roll paper storage space for applying side pressure is narrowed to substantially the same width as the roll paper.
Other objects and attainments together with a fuller understanding of the invention will become apparent and appreciated by referring to the following description and claims taken in conjunction with the accompanying drawings.
A roll paper printer is described below as a preferred embodiment of a printing device according to the invention with reference to the accompanying figures.
A roll paper holder 8 that is curved when seen from the side and opens to the top is disposed in the roll paper compartment 6, and the roll paper 7 is stored therein so that it can rotate on the roll paper holder 8. The detailed configuration of the roll paper compartment 6 is described below.
The roll paper 7 stored in the roll paper compartment 6 is delivered by a supply roller 9 from a point on the roll paper 7 at the back side of the printer. The web of recording paper supplied by the supply roller 9 travels around a tension roller 10 located above and to the back of the printer relative to the supply roller 9, passes over the surface of the platen 11 located directly above the roll paper compartment 6, and is conveyed from the back of the printer to the front of the printer.
A head carriage 13 on which the printhead 12 is mounted is disposed movably bidirectionally widthwise to the printer on a carriage guide shaft directly above the platen 11. The printhead 12 is an inkjet head, and the nozzle surface is opposite the top of the platen 11 with a constant gap therebetween. A paper feed drive roller 13A is disposed behind the platen 11, and a paper feed follower 13B is pressed from below to the paper feed drive roller 13A. A discharge drive roller 14A is disposed in front of the platen 11, and a discharge follower roller 14B is pressed from above to the discharge drive roller 14A.
The recording paper is conveyed passed the printing position defined on the top of the platen 11 toward the recording paper exit. The printhead 12 prints on the surface of the recording paper passing the printing position. The recording paper discharged by the discharge drive roller 14A and discharge follower roller 14B is cut widthwise by the fixed knife 15a and movable knife 15b of the paper cutter mechanism 15, which is located near the paper exit. The piece of recording paper (not shown in the figure) that is thus cut to a certain length may be issued as a receipt, for example.
As shown in
The access cover 4 is thus connected to the platen unit 17, and when the platen unit 17 is pulled forward the access cover 4 pivots on its bottom end and opens to the front. The roll paper holder 8 of the roll paper compartment 6 in this embodiment of the invention also rotates to a position tilted a specific angle towards the front of the printer as shown in
The roll paper loading mechanism 18 includes a platen support mechanism 19 that supports the platen unit 17 movably from the closed position 17A to the open position 17B, and supports the access cover 4 movably from the closed position 4A to the open position 4B. The platen support mechanism 19 includes a right platen support mechanism 19A disposed on the side on the right side of the roll paper printer 1 (see
The roll paper compartment 6 has a right side panel 25 (stationary side panel, see
The roll paper holder 8 is urged to the right side (in the direction of arrow A in
When the access cover 4 opens, the roll paper holder 8 pivots toward the front of the printer (in the direction of arrow B in
When the roll paper compartment 6 causes the roll paper holder 8 to pivot with the access cover 4 to the front of the printer, the left side panel 21 moves away from the right side panel 25, and when the access cover 4 is in the open position 4B, the left side panel 21 is at the position (second position) separated farthest from the right side panel 25. In addition, when the roll paper holder 8 pivots with the access cover 4 in the opposite direction, the left side panel 21 approaches the right side panel 25, and when the access cover 4 is in the closed position 4A, the left side panel 21 is at the position (first position) closest to the right side panel 25. As a result, side pressure can be applied to the roll paper 7 when the access cover 4 is closed, and when the access cover 4 is opened, the side pressure can be released and the width of the opening for dropping the roll paper into the roll paper compartment 6 is increased.
Because the linkage members of the right platen support mechanism 19A described above are disposed between the right side panel 25 and the right frame panel 27, the right side panel 25 is attached to leave a specific gap between the right side panel 25 and the right frame panel 27. The top of the front end 25a (the end facing the opening) of the right side panel 25 is recessed toward the back of the printer, and a basically trapezoidal roll paper guide tab 29 is formed protruding diagonally to the front right side of the printer. More specifically, the roll paper guide tab 29 is shaped so that the distance between it and the left side panel 21 increases with proximity to the distal end of the roll paper guide tab 29. In other words, the top of the front end of the right side panel 25 is bent to the outside (toward the right frame panel 27), and functions as the roll paper guide tab 29. The roll paper guide tab 29 protrudes diagonally to the front right side of the printer without touching the right frame panel 27.
In addition, because the right side panel 25 is stationary, all of the front end 25a including the roll paper guide tab 29 is positioned behind the front of the printer case 2. The roll paper 7 therefore cannot be positioned to the right side panel 25 on the outside of the printer case. However, because the front end of the roll paper guide tab 29 extends diagonally to the right front, roll paper 7 that is dropped in to a position passed the right side of the main part of the right side panel 25 can be guided by the roll paper guide tab 29 to the left side of the right side panel 25. Collision of the roll paper 7 being loaded with the front end of the right side panel 25 can therefore be suppressed, and the roll paper 7 can be dropped between the right side panel 25 and left side panel 21 even when the position where the roll paper 7 is dropped in is slightly offset. More specifically, the actual width of the opening for loading roll paper can be increased by providing this roll paper guide tab 29. As a result, dropping roll paper 7 into the roll paper compartment is not made difficult when the gap between the right side panel 25 and left side panel 21 is substantially the same as the width of the roll paper 7 along the rotational axis thereof, and roll paper can be easily loaded.
A support shaft (not shown in the figure) extending widthwise to the printer is disposed at a position on the back end of the platen unit 17. As shown in
The six-joint linkage mechanism 31 is described next with reference to
The six-joint linkage mechanism 31 has a first compound link 34 and a second compound link 35. The first compound link 34 includes a first link 34A and a second link 34B connected in series at a first pin joint 34C. The second compound link 35 includes a third link 35A (link member) and a fourth link 35B connected in series at a second pin joint 35C. The connections of the links in the first compound link 34 are shown schematically in
The second compound link 35 is located towards the back of the printer relative to the first compound link 34. More specifically, the bottom end of the first compound link 34 and the bottom end of the second compound link 35 are connected to a third pin joint 34D and a fourth pin joint 35D, respectively, at positions separated a specific distance in the front-back direction of the printer. Likewise, the top end of the first compound link 34 and the top end of the second compound link 35 are respectively connected by a fifth pin joint 34E and a sixth pin joint 35E to positions on the side of the platen unit 17 separated a specific distance in the front-back direction of the printer. The six-joint linkage mechanism 31 is thus rendered by these first to fifth links and first to sixth pin joints.
When the platen unit 17 is in the closed position 17A and the access cover 4 is in the closed position 4A, the first compound link 34 and second compound link 35 of the six-joint linkage mechanism 31 are folded together with the first pin joint 34C and second pin joint 35C where the links are connected projecting toward the front of the printer (see imaginary lines C and D in
After the compound links 34 and 35 are fully extended, the six-joint linkage mechanism 31 functions as a four-joint parallel linkage mechanism (see imaginary lines C and D in
The six-joint linkage mechanism 31 has a holding mechanism (not shown in the figure) for holding the first link 34A and second link 34B of the first compound link 34 in the substantially straight, fully extended position. Various configurations can be used as this holding mechanism, including a configuration that prevents the two links in the compound link from rotating to the opposite side after extending to the substantially straight position, a configuration that urges the pin joints connecting the two links toward the back of the printer by means of a tension springs or other means, a configuration that limits the path of motion of the pin joints connecting the links by means of a guide channel and guide pin, or other configuration.
As described above, because the roll paper guide tab 29 extends diagonally to the front right side of the printer, the path of the third link 35A moving rotationally in the space between the right frame panel 27 and right side panel 25 interferes with the roll paper guide tab 29. However, because the right side panel 25 is attached only at the bottom and back ends thereof, the top part of the front end 25a of the right side panel 25 where the roll paper guide tab 29 is formed is a free end that can move transversely, that is, toward and away from the left side panel 21, by means of deflection of the right side panel 25. Therefore, when the third link 35A passes the position overlapping the roll paper guide tab 29, the roll paper guide tab 29 can be escaped toward the left side panel 21 (in the direction of arrow F in
When the third link 35A moves away from the position overlapping the roll paper guide tab 29, deflection of the right side panel 25 ends and the roll paper guide tab 29 returns to its original position. In this embodiment of the invention, the position where the roll paper guide tab 29 is formed on the front end 25a of the right side panel 25 is set to a position not overlapping the third link 35A when the access cover 4 is open. As a result, when the roll paper 7 is dropped in, the roll paper guide tab 29 is not moved by interference with the third link 35A in the direction narrowing the size of the drop-in opening.
When the right side panel 25 is deflected by the third link 35A passing the position overlapping the roll paper guide tab 29, the right side panel 25 moves toward the left side panel 21 a distance corresponding to the amount of deflection. When the third link 35A is in this rotated position, the side pressure applied by the left side panel 21 is released by the side pressure release cam 26 described above. In this embodiment of the invention, the leftward movement of the left side panel 21 when side pressure is released by the side pressure release cam 26 (the distance between the first position and second position described above) is equal to the protrusion width L1 of the flat surface 26b shown in
When the access cover 4 is opened, the top of the third link 35A protrudes greatly forward from the front of the printer case 2 as shown in
In order for the roll paper 7 being loaded to be reliably pushed into position by the roll paper guide tab 29, the distal end 29a of the roll paper guide tab 29 only needs to protrude at least the thickness of the right side panel 25 (dimension t in
In this embodiment of the invention the urging force in the direction causing the top edge 35b of the left side 35a of the third link 35A to contact the right side panel 25 is applied to the third link 35A. More specifically, as shown in
Because the hook 39 is positioned higher than the position of the third link 35A when in the extended position shown in
Note that the guide channel 37A and guide channel 37B disposed behind guide channel 37A can be used to render the holding mechanism described above that holds the first link 34A and second link 34B substantially straight when fully extended.
Loading the roll paper into the roll paper compartment is described next with reference to
As shown in
If the roll paper 7 is successfully positioned on the left side of the left side 35a of the third link 35A and the roll paper 7 is dropped in from a position toward the back of the printer from the guide boss 41, the roll paper 7 falls onto the front of the bottom 20 of the roll paper holder 8, which is sloped steeply toward the inside of the roll paper compartment 6, and not onto the substantially horizontal surface contiguous to the platen 11. As a result, the roll paper 7 falls quickly to the inside of the roll paper compartment 6 without stopping at a position unsuitable as an entrance to the roll paper compartment 6.
However, if as shown in
(1) A platen support mechanism 19 (19A, 19B) including a guide mechanism that guides the platen unit 17 along a guide channel 32, and a six joint linkage mechanism that guides that guides the platen unit 17 along a curved path after moving along this guide channel 32, is used as a mechanism for opening and closing the access cover 4 and platen unit 17 in the foregoing embodiment, but a configuration using a four joint parallel linkage mechanism can be used instead. In this case, a link of the four joint parallel linkage mechanism can be configured identically to the third link 35A described above to achieve the same operation and effect.
(2) The embodiment described above describes applying the invention to a roll paper printer 1 that prints with an inkjet head, but the invention can be applied to other types of printers in which roll paper is loaded for printing. For example, the invention can also be applied to thermal printers, laser printers, and facsimile machines.
(3) A roll paper guide tab 29 is rendered only on the right side panel 25 in the embodiment described above, but an identically configured roll paper guide tab may also be formed on the left side panel 21.
Although the present invention has been described in connection with the preferred embodiments thereof with reference to the accompanying drawings, it is to be noted that various changes and modifications will be apparent to those skilled in the art. Such changes and modifications are to be understood as included within the scope of the present invention as defined by the appended claims, unless they depart therefrom.
Number | Date | Country | Kind |
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2010-103109 | Apr 2010 | JP | national |